First-choice left-back Ashley Cole is currently sidelined with a hamstring injury picked up in the FA Cup quarter-final win over Manchester United nine days ago and is not expected back until next week, along with centre-back Gary Cahill.

This leaves 18-year-old Nathan Ake as the Blues' only fit naturally left-sided defender ahead of the trip to Russia, with Chelsea defending a 3-1 first-leg lead.

Rafael Benitez had earlier confirmed the setback to reporters, and remains hopeful of a quick recovery: "The last thing I did [after training] was talk with the doctor on the pitch and I was asking her about Ryan, She said he would report and we will decide. Anyway we will put him on the list and we will see.

"He'd come in to train on the Saturday we played Southampton and we tested him then, but he was not feeling so well so we did the operation quickly on the meniscus.

"He and Ashley are both doing well, but the main thing is to see how they react when they come back on to the pitch and start running. Then we will see how quickly they progress."

Striker Demba Ba is cup-tied for the Europa League but still continues his own recovery after picking up an ankle injury in their recent win over Sunderland.

He added: "Demba did not train, just as a precaution, but it's not too serious, he will not go to Moscow. Hopefully he can train here and be okay for the weekend."